fs/hpfs/ea.c

   1 /*
   2  *  linux/fs/hpfs/ea.c
   3  *
   4  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
   5  *
   6  *  handling extended attributes
   7  */
   8
   9 #include "hpfs_fn.h"
  10
  11 /* Remove external extended attributes. ano specifies whether a is a
  12    direct sector where eas starts or an anode */
  13
  14 void hpfs_ea_ext_remove(struct super_block *s, secno a, int ano, unsigned len)
  15 {
  16         unsigned pos = 0;
  17         while (pos < len) {
  18                 char ex[4 + 255 + 1 + 8];
  19                 struct extended_attribute *ea = (struct extended_attribute *)ex;
  20                 if (pos + 4 > len) {
  21                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
  22                                 ano ? "anode" : "sectors", a, len);
  23                         return;
  24                 }
  25                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
  26                 if (ea->indirect) {
  27                         if (ea->valuelen != 8) {
  28                                 hpfs_error(s, "ea->indirect set while ea->valuelen!=8, %s %08x, pos %08x",
  29                                         ano ? "anode" : "sectors", a, pos);
  30                                 return;
  31                         }
  32                         if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 9, ex+4))
  33                                 return;
  34                         hpfs_ea_remove(s, ea_sec(ea), ea->anode, ea_len(ea));
  35                 }
  36                 pos += ea->namelen + ea->valuelen + 5;
  37         }
  38         if (!ano) hpfs_free_sectors(s, a, (len+511) >> 9);
  39         else {
  40                 struct buffer_head *bh;
  41                 struct anode *anode;
  42                 if ((anode = hpfs_map_anode(s, a, &bh))) {
  43                         hpfs_remove_btree(s, &anode->btree);
  44                         brelse(bh);
  45                         hpfs_free_sectors(s, a, 1);
  46                 }
  47         }
  48 }
  49
  50 static char *get_indirect_ea(struct super_block *s, int ano, secno a, int size)
  51 {
  52         char *ret;
  53         if (!(ret = kmalloc(size + 1, GFP_NOFS))) {
  54                 printk("HPFS: out of memory for EA\n");
  55                 return NULL;
  56         }
  57         if (hpfs_ea_read(s, a, ano, 0, size, ret)) {
  58                 kfree(ret);
  59                 return NULL;
  60         }
  61         ret[size] = 0;
  62         return ret;
  63 }
  64
  65 static void set_indirect_ea(struct super_block *s, int ano, secno a,
  66                             const char *data, int size)
  67 {
  68         hpfs_ea_write(s, a, ano, 0, size, data);
  69 }
  70
  71 /* Read an extended attribute named 'key' into the provided buffer */
  72
  73 int hpfs_read_ea(struct super_block *s, struct fnode *fnode, char *key,
  74                 char *buf, int size)
  75 {
  76         unsigned pos;
  77         int ano, len;
  78         secno a;
  79         struct extended_attribute *ea;
  80         struct extended_attribute *ea_end = fnode_end_ea(fnode);
  81         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
  82                 if (!strcmp(ea->name, key)) {
  83                         if (ea->indirect)
  84                                 goto indirect;
  85                         if (ea->valuelen >= size)
  86                                 return -EINVAL;
  87                         memcpy(buf, ea_data(ea), ea->valuelen);
  88                         buf[ea->valuelen] = 0;
  89                         return 0;
  90                 }
  91         a = fnode->ea_secno;
  92         len = fnode->ea_size_l;
  93         ano = fnode->ea_anode;
  94         pos = 0;
  95         while (pos < len) {
  96                 char ex[4 + 255 + 1 + 8];
  97                 ea = (struct extended_attribute *)ex;
  98                 if (pos + 4 > len) {
  99                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 100                                 ano ? "anode" : "sectors", a, len);
 101                         return -EIO;
 102                 }
 103                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return -EIO;
 104                 if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
 105                         return -EIO;
 106                 if (!strcmp(ea->name, key)) {
 107                         if (ea->indirect)
 108                                 goto indirect;
 109                         if (ea->valuelen >= size)
 110                                 return -EINVAL;
 111                         if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea->valuelen, buf))
 112                                 return -EIO;
 113                         buf[ea->valuelen] = 0;
 114                         return 0;
 115                 }
 116                 pos += ea->namelen + ea->valuelen + 5;
 117         }
 118         return -ENOENT;
 119 indirect:
 120         if (ea_len(ea) >= size)
 121                 return -EINVAL;
 122         if (hpfs_ea_read(s, ea_sec(ea), ea->anode, 0, ea_len(ea), buf))
 123                 return -EIO;
 124         buf[ea_len(ea)] = 0;
 125         return 0;
 126 }
 127
 128 /* Read an extended attribute named 'key' */
 129 char *hpfs_get_ea(struct super_block *s, struct fnode *fnode, char *key, int *size)
 130 {
 131         char *ret;
 132         unsigned pos;
 133         int ano, len;
 134         secno a;
 135         struct extended_attribute *ea;
 136         struct extended_attribute *ea_end = fnode_end_ea(fnode);
 137         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
 138                 if (!strcmp(ea->name, key)) {
 139                         if (ea->indirect)
 140                                 return get_indirect_ea(s, ea->anode, ea_sec(ea), *size = ea_len(ea));
 141                         if (!(ret = kmalloc((*size = ea->valuelen) + 1, GFP_NOFS))) {
 142                                 printk("HPFS: out of memory for EA\n");
 143                                 return NULL;
 144                         }
 145                         memcpy(ret, ea_data(ea), ea->valuelen);
 146                         ret[ea->valuelen] = 0;
 147                         return ret;
 148                 }
 149         a = fnode->ea_secno;
 150         len = fnode->ea_size_l;
 151         ano = fnode->ea_anode;
 152         pos = 0;
 153         while (pos < len) {
 154                 char ex[4 + 255 + 1 + 8];
 155                 ea = (struct extended_attribute *)ex;
 156                 if (pos + 4 > len) {
 157                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 158                                 ano ? "anode" : "sectors", a, len);
 159                         return NULL;
 160                 }
 161                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return NULL;
 162                 if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
 163                         return NULL;
 164                 if (!strcmp(ea->name, key)) {
 165                         if (ea->indirect)
 166                                 return get_indirect_ea(s, ea->anode, ea_sec(ea), *size = ea_len(ea));
 167                         if (!(ret = kmalloc((*size = ea->valuelen) + 1, GFP_NOFS))) {
 168                                 printk("HPFS: out of memory for EA\n");
 169                                 return NULL;
 170                         }
 171                         if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea->valuelen, ret)) {
 172                                 kfree(ret);
 173                                 return NULL;
 174                         }
 175                         ret[ea->valuelen] = 0;
 176                         return ret;
 177                 }
 178                 pos += ea->namelen + ea->valuelen + 5;
 179         }
 180         return NULL;
 181 }
 182
 183 /*
 184  * Update or create extended attribute 'key' with value 'data'. Note that
 185  * when this ea exists, it MUST have the same size as size of data.
 186  * This driver can't change sizes of eas ('cause I just don't need it).
 187  */
 188
 189 void hpfs_set_ea(struct inode *inode, struct fnode *fnode, const char *key,
 190                  const char *data, int size)
 191 {
 192         fnode_secno fno = inode->i_ino;
 193         struct super_block *s = inode->i_sb;
 194         unsigned pos;
 195         int ano, len;
 196         secno a;
 197         unsigned char h[4];
 198         struct extended_attribute *ea;
 199         struct extended_attribute *ea_end = fnode_end_ea(fnode);
 200         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
 201                 if (!strcmp(ea->name, key)) {
 202                         if (ea->indirect) {
 203                                 if (ea_len(ea) == size)
 204                                         set_indirect_ea(s, ea->anode, ea_sec(ea), data, size);
 205                         } else if (ea->valuelen == size) {
 206                                 memcpy(ea_data(ea), data, size);
 207                         }
 208                         return;
 209                 }
 210         a = fnode->ea_secno;
 211         len = fnode->ea_size_l;
 212         ano = fnode->ea_anode;
 213         pos = 0;
 214         while (pos < len) {
 215                 char ex[4 + 255 + 1 + 8];
 216                 ea = (struct extended_attribute *)ex;
 217                 if (pos + 4 > len) {
 218                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 219                                 ano ? "anode" : "sectors", a, len);
 220                         return;
 221                 }
 222                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
 223                 if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
 224                         return;
 225                 if (!strcmp(ea->name, key)) {
 226                         if (ea->indirect) {
 227                                 if (ea_len(ea) == size)
 228                                         set_indirect_ea(s, ea->anode, ea_sec(ea), data, size);
 229                         }
 230                         else {
 231                                 if (ea->valuelen == size)
 232                                         hpfs_ea_write(s, a, ano, pos + 4 + ea->namelen + 1, size, data);
 233                         }
 234                         return;
 235                 }
 236                 pos += ea->namelen + ea->valuelen + 5;
 237         }
 238         if (!fnode->ea_offs) {
 239                 /*if (fnode->ea_size_s) {
 240                         hpfs_error(s, "fnode %08x: ea_size_s == %03x, ea_offs == 0",
 241                                 inode->i_ino, fnode->ea_size_s);
 242                         return;
 243                 }*/
 244                 fnode->ea_offs = 0xc4;
 245         }
 246         if (fnode->ea_offs < 0xc4 || fnode->ea_offs + fnode->acl_size_s + fnode->ea_size_s > 0x200) {
 247                 hpfs_error(s, "fnode %08lx: ea_offs == %03x, ea_size_s == %03x",
 248                         (unsigned long)inode->i_ino,
 249                         fnode->ea_offs, fnode->ea_size_s);
 250                 return;
 251         }
 252         if ((fnode->ea_size_s || !fnode->ea_size_l) &&
 253              fnode->ea_offs + fnode->acl_size_s + fnode->ea_size_s + strlen(key) + size + 5 <= 0x200) {
 254                 ea = fnode_end_ea(fnode);
 255                 *(char *)ea = 0;
 256                 ea->namelen = strlen(key);
 257                 ea->valuelen = size;
 258                 strcpy(ea->name, key);
 259                 memcpy(ea_data(ea), data, size);
 260                 fnode->ea_size_s += strlen(key) + size + 5;
 261                 goto ret;
 262         }
 263         /* Most the code here is 99.9993422% unused. I hope there are no bugs.
 264            But what .. HPFS.IFS has also bugs in ea management. */
 265         if (fnode->ea_size_s && !fnode->ea_size_l) {
 266                 secno n;
 267                 struct buffer_head *bh;
 268                 char *data;
 269                 if (!(n = hpfs_alloc_sector(s, fno, 1, 0, 1))) return;
 270                 if (!(data = hpfs_get_sector(s, n, &bh))) {
 271                         hpfs_free_sectors(s, n, 1);
 272                         return;
 273                 }
 274                 memcpy(data, fnode_ea(fnode), fnode->ea_size_s);
 275                 fnode->ea_size_l = fnode->ea_size_s;
 276                 fnode->ea_size_s = 0;
 277                 fnode->ea_secno = n;
 278                 fnode->ea_anode = 0;
 279                 mark_buffer_dirty(bh);
 280                 brelse(bh);
 281         }
 282         pos = fnode->ea_size_l + 5 + strlen(key) + size;
 283         len = (fnode->ea_size_l + 511) >> 9;
 284         if (pos >= 30000) goto bail;
 285         while (((pos + 511) >> 9) > len) {
 286                 if (!len) {
 287                         if (!(fnode->ea_secno = hpfs_alloc_sector(s, fno, 1, 0, 1)))
 288                                 goto bail;
 289                         fnode->ea_anode = 0;
 290                         len++;
 291                 } else if (!fnode->ea_anode) {
 292                         if (hpfs_alloc_if_possible(s, fnode->ea_secno + len)) {
 293                                 len++;
 294                         } else {
 295                                 /* Aargh... don't know how to create ea anodes :-( */
 296                                 /*struct buffer_head *bh;
 297                                 struct anode *anode;
 298                                 anode_secno a_s;
 299                                 if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
 300                                         goto bail;
 301                                 anode->up = fno;
 302                                 anode->btree.fnode_parent = 1;
 303                                 anode->btree.n_free_nodes--;
 304                                 anode->btree.n_used_nodes++;
 305                                 anode->btree.first_free += 12;
 306                                 anode->u.external[0].disk_secno = fnode->ea_secno;
 307                                 anode->u.external[0].file_secno = 0;
 308                                 anode->u.external[0].length = len;
 309                                 mark_buffer_dirty(bh);
 310                                 brelse(bh);
 311                                 fnode->ea_anode = 1;
 312                                 fnode->ea_secno = a_s;*/
 313                                 secno new_sec;
 314                                 int i;
 315                                 if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9), 1)))
 316                                         goto bail;
 317                                 for (i = 0; i < len; i++) {
 318                                         struct buffer_head *bh1, *bh2;
 319                                         void *b1, *b2;
 320                                         if (!(b1 = hpfs_map_sector(s, fnode->ea_secno + i, &bh1, len - i - 1))) {
 321                                                 hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 322                                                 goto bail;
 323                                         }
 324                                         if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
 325                                                 brelse(bh1);
 326                                                 hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 327                                                 goto bail;
 328                                         }
 329                                         memcpy(b2, b1, 512);
 330                                         brelse(bh1);
 331                                         mark_buffer_dirty(bh2);
 332                                         brelse(bh2);
 333                                 }
 334                                 hpfs_free_sectors(s, fnode->ea_secno, len);
 335                                 fnode->ea_secno = new_sec;
 336                                 len = (pos + 511) >> 9;
 337                         }
 338                 }
 339                 if (fnode->ea_anode) {
 340                         if (hpfs_add_sector_to_btree(s, fnode->ea_secno,
 341                                                      0, len) != -1) {
 342                                 len++;
 343                         } else {
 344                                 goto bail;
 345                         }
 346                 }
 347         }
 348         h[0] = 0;
 349         h[1] = strlen(key);
 350         h[2] = size & 0xff;
 351         h[3] = size >> 8;
 352         if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l, 4, h)) goto bail;
 353         if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l + 4, h[1] + 1, key)) goto bail;
 354         if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l + 5 + h[1], size, data)) goto bail;
 355         fnode->ea_size_l = pos;
 356         ret:
 357         hpfs_i(inode)->i_ea_size += 5 + strlen(key) + size;
 358         return;
 359         bail:
 360         if (fnode->ea_secno)
 361                 if (fnode->ea_anode) hpfs_truncate_btree(s, fnode->ea_secno, 1, (fnode->ea_size_l + 511) >> 9);
 362                 else hpfs_free_sectors(s, fnode->ea_secno + ((fnode->ea_size_l + 511) >> 9), len - ((fnode->ea_size_l + 511) >> 9));
 363         else fnode->ea_secno = fnode->ea_size_l = 0;
 364 }
 365